Level measurement

Overview measuring principles

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Hydrostatics (pressure) Hydrostatic level measurement in open tanks is based on the determination of the hydrostatic pressure which is generated by the height of the liquid column. The obtained pressure is thus a direct measure for the level.

Cerabar, Deltapilot Unaffected by dielectric constant, foam, turbulence and obstacles. Condensate-proof, watertight and long-term stable Contite measuring cell with optimized temperature shock behavior (Deltapilot).

• Process temperatures up to +400°C/+752°F

Hydrostatics (differential pressure) In closed, pressurized tanks, the hydrostatic pressure of the liquid column causes a difference in pressure. The same leads to a deflection of the measuring element which is proportional to the hydrostatic pressure.

Deltabar Unaffected by dielectric constant, foam, turbulence and obstacles. High overload resistance. • Process temperatures up to +400°C/+752°F • Process pressures up to 420bar/6,090psi • Unaffected by ambient temperatures (Deltabar electronic dp)

Capacitance The principle of capacitive level measurement is based on the capacitance change of a capacitor. The probe and the tank wall form a capacitor whose capacitance is dependent on the amount of product in the tank: an empty tank has a lower, a filled tank a higher capacitance.

Liquicap Exact measurement from the end of the probe to the process connection without any blocking distance. Very fast response times. Unaffected by density, turbulence and vapor pressure.

• Process temperatures up to +200°C/+392°F • Process pressures up to 100bar/1,450psi

Radiometry The gamma source, a cesium or cobalt isotope, emits radiation which is attenuated as it passes through materials. The measuring effect results from the absorption of radiation by the product to be measured which is caused by level changes. The measuring system consists of a source and a compact transmitter as a receiver.

Gammapilot Compact transmitters in different measuring lengths, adaptable measuring ranges. Non-contact measurement from outside for all extreme applications, abrasive media. • Unaffected by media • Any process temperature • Any process pressure • Unaffected by gammagraphy (Modulator)